The words “Miss America” conjure up associations of big smiles, homegrown patriotism and innocent, all-American glitz. Mystery and illicit romance don’t usually factor into it. But not many people remember the story of the runaway Miss America 1937 winner Bette Cooper of New Jersey. Author Michael Callahan tapped into her little-known but fascinating history to inspire his new novel, “The Night She Won Miss America”. Here, exclusively for The Post, he tells the true story of the beauty queen who abandoned her crown for forbidden love.

She didn’t want to do it.

In the summer of 1937, blonde, pixieish Bette Cooper, the 17-year-old daughter of a state highway engineer in rural Hackettstown, NJ, had come with some girlfriends to nearby Bertrand Island, an amusement park boasting a roller coaster and not much else. That night, the park was hosting a surprise beauty pageant for “Miss Bertrand Island,” with the winner scoring a covetous prize: a chance to represent New Jersey at the Miss America pageant in Atlantic City in September.

Founded in 1921, the pageant had started out as a slightly schlocky bathing-beauty contest meant to extend the summer tourist season; but 16 years later, it was an American institution, its crownings dutifully recorded in newsreels and reported on the radio.

Bette was shy and demure, with a thin voice and a sunny smile — not at all the archetypal leggy, buxom beauty queen with teased-out hair that would become the pageant’s iconographic image for the next five decades. But like many a teenager before and since, she accepted the dare from her peers, and to everyone’s surprise — no one’s more than her own — Bette won.

Her parents were agog at the news. What to do? They were reluctant to throw their youngest child into the whirlwind of a week-long spectacle in a town that had most recently made headlines for a raid on its brothels. But in the end a family vacation by the sea, and a chance to cheer on their daughter, won out.

Any misgivings they might have retained quickly vanished when they arrived in Atlantic City and met Bette’s assigned escort for the week, a dashing 21-year-old named Louis Off, whose family owned the Brighton Hotel as well as a nursery that provided flowers to almost every hotel in the resort town. He was handsome, well spoken, polite. He wore tailored clothes and drove a maroon Buick convertible.

Bette CooperBettmann Archive

And so the Coopers thought: What could go wrong?

The practice of assigning young college men from the area’s better families to squire the girls around for the week was a practice that was far more practical than it was romantic. In the throes of the Great Depression the organizers of the Miss America pageant were, like everyone else, scrambling for money to stay solvent. Organizers thought having young men chauffeur and entertain their contestants for the week was a cost-cutting idea both cunning and winning. The girls got a taste of seaside flirtation; the boys got to spend time with pretty girls; the pageant got free labor. Everybody won.

Lou Off had been late to sign up for his contestant — by the time he and a friend arrived at pageant headquarters only two girls were left: Miss New Orleans and Miss Bertrand Island, NJ. Ever gallant, Lou let his pal pick first; predictably, the friend opted for whom he hoped would prove to be a saucy Southern belle. That left Lou with Bette, the teenage Shirley Temple look-alike who still seemed startled to be there in the first place.

Lou couldn’t believe his luck. As he would tell Frank Deford for “There She Is: The Life and Times of Miss America,” the writer’s 1971 book about the pageant, “In this crowd, Bette stood out like a beacon light in the middle of the ocean.” He sent her orchids every day.

I don’t want to be known as Mr. Miss America

As Bette and Lou spent time together during the week, their fledgling romance appeared to be largely one-sided: Bette, moony and immature, seemed thunderstruck by her charming date, while Lou viewed the whole thing as more of a lark (even if his daily orchids indicated otherwise). In between various photo sessions and obligatory appearances, Bette adored her drives, picnics and beach walks with Lou, and wasn’t shy about showing it.

For the better part of the week she had been suffering with a head cold, at one point even seeking a physician’s care. But that didn’t stop her from going from dark horse to major contender with a lovely rendition of “Where the Poppies Bloom Again” during pageant preliminaries — a feat quickly matched by her surprise win in the preliminary evening gown competition. People were beginning to wonder if she might be able to take the crown and sash.

Everyone, that is, except Bette. The Saturday afternoon just before the splashy Saturday night pageant itself, Lou drove Bette out to a sleepy restaurant in Somers Point, down past Absecon Island, and asked her the question she had dared not ask herself: “Have you thought about what you are going to do if you win?”

Bette thought the idea preposterous. What was he talking about?

A betting man, Lou knew better. He later recalled to Deford (and confirmed to me, when I talked to him many years later) that he told Bette, “I just want to let you know now that if you do win, you can forget about me, because I don’t want anything to do with it. The last thing in the world I want is publicity.”

Lou Off holding a shot of Bette Cooper, Miss America, Sept. 10, 1981.Press of Atlantic City

He added: “I don’t want to be known as Mr. Miss America.”

The conversation veered elsewhere. But the threat hung over the lovesick Bette Cooper like a sword.

And then she won.

Defying the predictions of almost everyone, Bette Cooper, the kewpie doll waif from New Jersey, bested Southern heavyweights Miss Texas and Miss North Carolina in the final round of three to earn the crown and the title of Miss America 1937. She gushed “I’m so happy” as flashbulbs popped, and posed in her ermine-trimmed cape and slightly lopsided crown, which seemed more fit for a court jester than a beauty queen.

Her happiness would prove to be exceptionally short-lived.

Bette CooperBettmann Archive

True to his word, Lou broke it off that very evening, bolting from the coronation ball and vanishing into the night. Heartsick and inconsolable, Bette retreated to her suite at the Lafayette Hotel accompanied by her parents, who seemed gobsmacked by both their daughter’s unlikely victory and her distress at losing Lou.

At 2 a.m. the phone in Lou Off’s apartment at the Brighton rang. It was Bette, sobbing, telling him he had to come. He had to. She insisted she did not want the title after all.

(Years later, in a rare comment about the entire affair, Bette insisted it was her parents, more than she, who wanted her to abdicate her title; Lou told me he remembered Bette wanted out.)

Lou called two friends, bundled Bette up, and, as the sun was just beginning to rise, escorted the new Miss America down the fire escape of the hotel and into his car, where they would eventually drive to his motorboat moored some two miles away.

It was a bright and beautiful Sunday in Atlantic City, and Lenora Slaughter, the iron butterfly who had come up from Florida two years earlier to whip the pageant into professional shape, was making sure everything was in order on the famous Steel Pier: a red velvet throne had been obtained, and there were assorted dignitaries, reporters and runners-up milling about, waiting for the appearance of the new Miss America. Then the whispers started.

Miss America was missing.

Calls to her room went unanswered. The Coopers threw up their hands, professing no knowledge of where their daughter might be. A police official pledged to leave no stone unturned in the search for her. The press scattered to the four winds of the Boardwalk, frantically pursuing the story of the Miss America who had vanished. A few dashed up to her room, looking for clues, but found none. Until one of them overheard a hotel maid, lazily dusting, casually remark, “There was a young man. Sent her orchids every day.”

The young man and the wayward titleholder were, in fact, moored in his boat some 200 feet off of the Steel Pier. Lou had correctly calculated that hiding in plain sight offered them their best chance to elude the authorities. Bette, exhausted, slept most of the day, until that night when she clambered into Lou’s car, and he drove her home to Northern New Jersey. On the way home, Lou heard Walter Winchell on the radio, issuing a report that he and Bette had . . . eloped.

Bette Cooper (far right) stands next to the four girls from whom were selected Miss America of 1937.Bettmann Archive

It was all over soon enough, including Lou and Bette’s fledgling romance. (Lou has said that the two briefly dated again years later.) Furious and mortified when the true details of the night emerged, pageant officials issued threats for what would happen if Bette didn’t fulfill her Miss America duties, and a chilly détente was struck: She managed a few feeble appearances and interviews during her “reign,” before happily turning the title over to Miss Ohio the next September.

Perhaps predictably, Lou Off was rather loathed by pageant folk. (“They hated my guts,” he told me when I spoke to him in the mid-1990s.) He remained at the Jersey Shore, and eventually married and took over his family’s nursery business.

As for Bette, after her tumultuous adventure, she did in 1938 what she had done that unforgettable night in 1937 — she effectively disappeared. She steadfastly refused to participate in any Miss America activities ever again, and at points, when tracked down by pesky reporters, openly disavowed she had even been Miss America at all. She married and had children and as of press time is living quietly in suburban Connecticut at the age of 96.

Her legacy is one of infamy, and of one long, lasting change still in effect today. In 1938, the pageant discontinued the escort program.